针对激光加工大功率激光功率密度分布测量的要求,采用空心探针扫描采样测量法,提出并建立了被测激光经探针小孔、探针内通道传输的数学物理模型,经计算,给出了包括探针微孔孔径、探针内通道尺寸、系统采样点数等系统参数,设计了新的测量系统,实现了对大功率激光光束、聚焦光斑功率密度分布的直接测量,测量结果与理论计算相吻合.测量仪能对CO2激光和YAG激光进行直接测量,测量的功率大于10 kW,功率密度大于107 W/cm2,测量激光光束的最大直径为60 mm,激光聚焦光斑的直径小于0.5 mm.

Using the method of rotating needle pinhole, the measuring system which can directly measure the high dense laser transverse intensity distribution of laser beams/focus for laser processing is developed. The mathematical and physical models of measured laser beams/focus propagation in needle pinhole are established. According to the calculation, the system parameters, including aperture of needle pinhole, dimension of propagation channel, dot number of sampling, are given. A new measuring system is designed. The measuring of high power laser beams/focus by this system is realized. The calculation results are of agreement with the measuring results. The instrument can measure CO 2 and YAG laser, measured power larger than 10 kW, maximal measured power density up to 10 7 W/cm 2, measured laser beam maximal diameter is 60 mm, measured laser focus minimal diameter smaller than 0.5 mm.